Renesas SH7709S - page 588

Rev. 5.00, 09/03, page 544 of 760

Figure 16.7 shows an example of the operation for transmission.

1 1

0/1 0 1

TDFE

TEND

Parity

bit

Parity

bit

Serial

data

Start

bit Data

Stop

bit

Start

bit Data

Stop

bit

Idle (mark

)

state

TXI interrupt

request

Data written to

SCFTDR and TDFE

flag read as 1 then

cleared to 0 by TXI

interrupt handler

One frame

D0D1D7D0D1D70/1

TXI interrupt

request

Figure 16.7 Exam p l e of Tra nsmit Operation

(8-Bit Data, Parity, One Stop Bit)

4. When modem control is enabled, transmission can be stopped and restarted in accordance with

the CTS input value. When CTS is set to 1, if tr ansmissi on is in progress, the line goes to the

mark state after transmission of one frame. When CTS i s se t to 0, the nex t tra nsmit data is

output starting from the start bit.

Figure 16.8 shows an example of the operation when modem control is used.

0 0/1 0

CTS

Parity

bit

Serial

data

TXD

Start

bit

Stop

bit

Start

bit

D0D1D7D0D1D70/1

Rise at this point

before stop bit

Figure 16.8 Example of Operation Using Modem Control (C